The present invention generally relates to testing at least one semiconductor product. More particularly, the present invention relates to analyzing test results of at least one semiconductor product.
A semiconductor product includes, but is not limited to a semiconductor chip, a semiconductor wafer and a semiconductor wafer lot. An individual semiconductor tester includes, but is not limited to an Automatic Test Equipment (ATE) station. An ATE station refers to any automated device that is used to test printed circuit boards, semiconductor wafers, semiconductor chips, integrated circuits (ICs) or any other electronic components. Agilent® Medalist i1000D, Agilent® Medalist i3070, Teradyne® Catalyst, Teradyne® Tiger, Teradyne® FLEX and Teradyne® UltraFLEX are examples of commercially available ATE stations.
An ATE station requires an active monitoring to ensure that the tester (ATE station) and/or a test program (i.e., a software program directing the tester) are operating under proper conditions. These conditions involve appropriate control of mechanical, physical, electrical, programmatic and environmental aspects. Some examples of these conditions include a proper calibration of the tester, probe instrument cleanliness and alignment, proper test limits and test parameters applied during the testing, and proper environment temperature settings. The probe instrument is part of the device interface board (DIB) that is used to connect the semiconductor device under test (DUT) to the tester. For example, a tester's pin parametric measuring units need the probes to be in proper condition to properly measure electrical characteristics. Control and monitoring problems encountered in the testing lead to wasted resources including, but not limited to: a semiconductor product loss, an increased test time, increased labor hours (i.e., increased labor cost), overly stressed equipment, augmented schedules, improperly tested devices, and increased cost.
Therefore, it is highly desirable that the testing is properly operated, monitored, and controlled either manually by operators or automatically using systems for Statistical Process Control (SPC) and Adaptive Test.